Cardiocirculatory aiding devices are generally well known in the practice of cardiosurgery. These devices, which include various types of mechanical devices for aiding the functioning of the heart, are commonly referred to as a Ventricular Assist Device (V.A.D.) or Total Artificial Heart (T.A.H.). Such devices are able to mechanically pump the blood, thereby producing pulse or continuous hematic flows.
Such devices can be used to solve reversible acute cardiac insufficiencies (e.g.: infarct, myocarditis, morphological pathologies, postcardiotomy, etc.), or are used for supporting the circulatory function while one awaits a heart transplantation, or even indefinitely in situations of irreversible, chronically problematic pathologies (i.e., “Therapy destination”).
Different ventricular aid devices have been present for many years, for both the left and the right, and for biventricular (T.A.H.). Some of them are commercially available, while others have been developed only on an experimental level. However, these existing designs suffer from a number of drawbacks.
In most cases, the existing devices have some difficulties in terms of positioning the device inside the chest, due primarily to dimension and weight problems, as well as in the application modalities. Other common drawbacks result from their internal geometries and their pumping modalities, which will sometimes cause hemolysis or the formation of coagulations.
A significant negative aspect of the known devices is their undesirable weight and the encumbrance of the operating unit, particularly with respect to the pumping device, which generally limits or precludes the portability of the entire device. More significantly, however, is that existing devices are simply too large for certain individuals. Today, a ten pound child experiencing heart failure has little or no hope. However, if a small enough device could be employed, it could be implanted into a small child, giving his or her heart a chance to heal and grow, after which the device could then be removed. Similarly, a one hundred pound woman experiences the same size and installation problems associated with the existing devices and would likewise benefit from a smaller device than is currently available.
An additional problem created by the current devices is that they include complex internal mechanisms and, given this complexity, they are not completely reliable. In fact, it is known that, the more complex an apparatus is, the greater the likelihood the device will experience jamming, which, of course, is very dangerous. When the device jams or stops, it is unlikely the individual will be able to obtain immediate medical assistance to intervene, and thus, such incidents will often prove fatal.
Moreover, this complexity adds other dangers, as such devices will typically incorporate an electrical and/or electromagnetic apparatus, with all the obvious potential dangers accompanying such, while some devices require that separate parts be housed in different positions of the body, resulting in other surgical complications, undesirable encumbrances, and the danger of infection.
What is desired, therefore, is a device that efficiently, reliably, and safely pumps blood to assist the heart. What is further desired is a device that can be used in small areas. What is also desired is a device that is as mechanically uncomplicated as possible.